Of all five senses, vision is most important for helping humans perceive and interpret our surroundings. Other animals are more reliant on their sense of smell. For us, eyes are the main sense organ, and much of our brain activity is a dedicated to visual input.
When eyesight is compromised, the result can be devasting. Severe vision loss that cannot be repaired with corrective lenses, medication or surgery, is called low vision. This extreme health condition is defined by the WHO as under 20/70 vision in the strongest eye, even with the best sight correction possible.
Common Causes of Low Vision
- Age-related Macular Degeneration (AMD): The macula is the central part of the retina, which deteriorates with age. Since the retina is responsible for sharp focus on close objects, it determines what we see clearly in our center of vision. AMD impacts driving ability, facial recognition, reading, and work with fine detail. Macular degeneration is the leading cause of blindness in patients over 50 in the United States. It is also responsible for about 50 percent of low vision cases.
- Glaucoma: This group of eye disorders eventually affects the optic nerve. The build-up of fluid cause pressure in the eye leading to damage and vision loss. Glaucoma develops due to drainage issues, too much fluid or problems with the release of fluid. This eye health condition is the second leading cause of blindness. Early detection is key to slowing down the progression of glaucoma and minimizing vision loss.
- Retinitis Pigmentosa (RP): This grouping of eye diseases will destroy both peripheral and night vision over time. RP will progressively damage the light-sensitive rods and cones in the back of the eye. This is an inherited disease that is first presented as night blindness in adolescent or early adult years. Unfortunately, patients diagnosed with RP typically reach total blindness by age 40.
- Diabetic Retinopathy: About 45 percent of diabetic patients are diagnosed with retinopathy. This eye condition causes retina damage gradually, and if left untreated, total blindness. Blood sugar fluctuations can damage blood vessels in the eye, causing the retina to swell. The result is cloudy or blurry vision. The best defense is to regulate blood sugar levels.
- Amblyopia: The common term is a lazy eye, it affects the developing of one eye early in life. There is no eye health issue to blame; one eye just fails to develop properly in childhood. The key to reversing lazy eye is early diagnosis and treatment. Therefore, infants should have their first comprehensive eye exam by six months old, and another at age three. Without early treatment, the condition cannot be reversed.
- Traumatic Brain Injury: Stroke, head trauma, and brain injuries can all cause a shift in the visual field, blurry vision, problems with depth perception, reduced visual acuity, eye misalignment, and glare sensitivity.
- Cataracts: When the eye lens develops a cloudy film, light cannot get back to the retina. This causes vision loss. Cataracts are caused by genetic, injury, disease, sun exposure, injury and advanced age. The opaque layer can be surgically removed and replaced with a prosthetic lens to restore clear vision.
Many of these eye conditions and diseases can be treated and controlled if caught early. The most important step is to keep up with annual eye exams to help safeguard your eye health and help prevent low vision.